Digital watermarking is an increasingly desired, but (in this author's opinion) conceptually flawed cryptographic technique. Overwhelmingly, digital watermarking is proposed as a way to prevent (or at least identify) unauthorized reproduction of digital information. A prominent and recent example is the Recording Industry Association of America's (RIAA) Secure Digital Music Initiative (SDMI). The idea behind a digital watermark is to scatter some bits into a digital file in such a way that the scattered bits cannot be identified by an attacker, and therefore cannot be removed or altered without making the changes evident (in the case of analog source media, such as sound, video, and images, this amounts to assuring unacceptable degradation of the quality of the source).